A method of the type described above is known from publication DE 198 17 852 A1, which is used to produce coils of spools with surfaces sloped toward one another. In this process, the photosensitive resist coating is applied to the spools by spraying. Following structuring of the photosensitive resist coating, copper is electrolytically deposited onto the spool, thereby forming the windings of the spool. In this process, the structuring of the photosensitive resist coating is performed using lithography with inclined surfaces.
The drawback of the known method is that the spray application of a photosensitive resist precludes the production of a uniform coating thickness across the entire spool. In particular, the thickness of the coating varies very considerably at contact edges between flat surfaces of the spool. This causes problems during exposure of the photosensitive resist, since different coating thicknesses also require different exposure times. However, varying exposure times can only be achieved at a very high cost.
Another drawback of the known method is that a photosensitive resist coating applied by spraying tends to tear out after hardening, particularly at the contact edges between the flat surfaces of the spool. This can result in short-circuits during subsequent electroplating of the strip conductors.